Hi guys, On Wed, Oct 5, 2011 at 11:19 AM, Steve Sakoman <sakoman@xxxxxxxxx> wrote: > On Wed, Oct 5, 2011 at 9:26 AM, Tony Lindgren <tony@xxxxxxxxxxx> wrote: >> * Dave Hylands <dhylands@xxxxxxxxx> [111004 23:41]: > >>> I then also had to modify drivers/mmc/card/block.c and initializing >>> disable_multi to 1 in the mmc_blk_issue_rw_rq function to get rid of >>> the following messages for every I/O request. >>> >>> mmcblk0: retrying using single block read >>> mmcblk0: retrying using single block read >>> mmcblk0: retrying using single block read >>> mmcblk0: retrying using single block read >>> >>> (since this revision of the silicon doesn't support multi-block MMC reads). >> >> ..but this one is usually a problem muxing the MMC data lines. >> >> Are you sure this revision only supports one data line? > > No, I think you misunderstood the issue! > > The issue is that multi-block mmc reads are broken and the code falls > back to single block reads but prints a warning each time. > > Looking for a definitive source for this errata with Google I find: > > "According to the TI docs, multiple block read transfer > does not work correctly in CPU revisions 2.1 and earlier (TI advisory > 2.1.1.128)." > > So the correct fix is probably to use multi-block reads only on > revisions post 2.1. And uboot does a very specific check for the silicon revision and only does single block reads. http://git.denx.de/?p=u-boot.git;a=blob;f=drivers/mmc/omap_hsmmc.c;h=5d4cf51104a7936377dc27a2f18e8240ada9a24a;hb=HEAD#l497 (look at line 497) -- Dave Hylands Shuswap, BC, Canada http://www.davehylands.com -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
